Figure 10.

NAC pre-treatment abrogates CHOP and DR4 activation by curcumin or curcumin/TRAIL combination. ACHN cells were pre-treated with 0.5% DMSO-containing culture medium, 50 ng/mL TRAIL, 25 µM curcumin or a co-treatment of 50 ng/mL TRAIL + 25 μM curcumin. The cells were pre-treated with 10 mM N-acetyl cysteine (NAC) for 1 h to block ROS activity prior to exposure to the various treatments for 24 h. Whole cell protein was extracted at 24 h with RIPA buffer. Equal amounts of protein were separated by SDS-PAGE electrophoresis, transferred to nitrocellulose and indirectly probed for (a) DR4 and (b) CHOP using monoclonal antibodies and an ECL detection system. GAPDH was used as a loading control. *, ** and *** indicate statistically significant differences from respective controls at p < 0.05, p < 0.01 and p < 0.01. One-way ANOVA was used to analyse the data.